Figure 2. Effect of charges on the PrP hydrodynamic features.

(a) Mass size distributions of PrP wt and PrPΔ23–89 as a function of pH and NaCl concentration. The theoretical values of R_H for spheres with similar MWs to PrP wt and PrPΔ23–89 are 2.25 and 1.96 nm, respectively. (b) Mass size distributions of PrP mutants in 10 mM NaAc pH 4.5 (black) and 10 mM Mes pH 6.5 (green). The measurements were performed at 25 °C using at least two different protein batches. Column widths show the standard deviation among measurements. Arrows at the top indicate the different R_H values.